Ion-induced damage in apatite irradiated at ambient & high pressure conditions
نویسندگان
چکیده
In geological minerals, tracks of fragments from spontaneous fission of U nuclei accumulate over geological time scales and are widely used for fission-track dating and thermochronology [1, 2]. In our recent studies, we tackled the problem how solids exposed to energetic heavy ions cope with the simultaneous exposure of external pressure. This combination of ion irradiation and pressure is suitable for simulating the conditions fission fragments experience in the interior of the Earth [3]. A single crystal of Durango apatite was pressurized to 10.5 GPa between two ~1.4-mm thick diamonds of a diamond anvil cell (DAC) and irradiated at the SIS with 5×10 cm Kr ions of initial energy 106 MeV/u corresponding to 25 MeV/u at the sample site. For comparison, we also exposed non-pressurized apatite samples to U ions of 11.1 MeV/u at the UNILAC.
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